There are many Once Removed situations where you are in a tidal wave at the completion of the call part of the concept/call.

This situation is practically impossible to resolve for most dancers because they have no idea of their position in any tidal formation. Additionally, there is no time for each person to resolve his or her position within the tidal formation within the time allotted for the call.

When a Once Removed call ends in a tidal formation, dancers are required to adjust their positions to become Once Removed from others in their group. There are three ways to adjust; the couples in the center wave slide by each other, each wave centers Slither or both of them in that order.

The two movements have names - the very center two couples sliding by each other is called DRAG. The Slither done by the very centers of each wave is called a DROP.

DRAG and DROP have evolved because they are workable solutions to this problem - How do we get everyone Once Removed from each other when they probably didn't know who they were Once Removed from and who was in their Once Removed group to begin with. DRAG and DROP are survival tactics. They are used when the call follows Once Removed types 2 and 3 discussed in the Once Removed Types section.